This invention relates generally to control levers used on machinery such as agricultural tractors to operate hydraulic devices and, more particularly, to a mechanism cooperable with the control lever to limit the movement thereof and, thereby, restrict the operation of the corresponding hydraulic device.
One rotatable control lever position control apparatus is disclosed in U.S. Pat. No. 4,548,094, issued to Thomas W. Hultema, et al, on Oct. 22, 1985. This apparatus is in the form of a cylinder having notches formed therein to engage the control lever passing therethrough and limit the movement of the control lever in accordance with the notch aligned with the control lever. The cylinder is provided with a thumb wheel member that projects upwardly through the control panel for rotation by the operator to select the respective notch to be aligned with the control lever.
It is desirable to provide an alternative control lever position control mechanism having a more positively engageable pivotal actuation lever for manipulation by the operator to select the various modes of operation of the hydraulic system. Furthermore, it would be desirable to provide an alternative position control mechanism that would be operable to select a greater range of hydraulic system modes of operation.